Design method for characteristic simulation part of turbine blade root trailing edge and characteristic simulation part

Abstract

The present disclosure provides a method for designing a characteristic simulation component of the root trailing edge of a turbine blade and the characteristic simulation component, belonging to the technical field of aeroengines and gas turbines. When constructing the characteristic section of the blade body, this method shows the variation characteristics of the sectional average stress of the blade body with the height of the blade body through variable cross-section design, and when constructing the characteristic section of the root trailing edge, it combines geometric characteristics and the stress, strain distribution, maximum stress gradient and other characteristics of its dangerous parts. While simplifying the design and reducing the processing cost, it can accurately simulate the stress concentration situation of the local part of the blade, effectively avoid the damage of the non-target area of the characteristic simulation component of the root trailing edge of the turbine blade during the test, reduce the test difficulty and improve the test effectiveness at the same time.

Description

Technical Field

[0001] The present disclosure relates to the technical field of aeroengines and gas turbines, and particularly relates to a design method for a characteristic simulation component of a turbine blade root trailing edge and the characteristic simulation component. Background Art

[0002] The turbine blade is a core component of the engine rotor in an aeroengine and a gas turbine, having complex internal chambers and geometric configurations, and being subjected to the combined action of complex loads such as centrifugal force, air flow, and high temperature. In the turbine blade, the overall thickness of the root trailing edge is relatively thin, large stress regions are easily generated, and there is also a trailing edge split structure, making it prone to fatigue failure and damage, affecting the working safety and service life of the aeroengine and the gas turbine. Therefore, accurately characterizing the state of the turbine blade under complex loads to study its fatigue problem is crucial for the overall structural design of the aeroengine and the gas turbine.

[0003] Currently, for the fatigue problem of turbine blades, it is often achieved by designing a simulation component to simulate its characteristics and conducting a load test based on this simulation component. The turbine blade mainly includes structures such as a blade body, a blade root, a shroud, a root extension, and a dovetail. Among them, the blade body mainly realizes the aerodynamic performance of the blade by adopting different cross-sectional shapes at different heights; the blade root has a chamfered structure and serves as a transition section between the blade body and the shroud; the shroud is used to form an independent air flow channel to prevent high-temperature gas from entering other regions and usually has a square extended platform structure; the root extension serves as a transition section between the shroud and the dovetail, and the dovetail is connected to the turbine disk to transmit power to the rotor connected to the turbine disk.

[0004] Existing simulation components usually mainly consider simulating the geometric characteristics of the turbine blade, having problems of complex design, high processing cost, and great test difficulty; and they focus on the design of geometric characteristics, which may make the stress concentration phenomenon in the simulation component not obvious during testing, resulting in damage to non-target regions and affecting the accuracy of the test results.

[0005] The above information disclosed in the background art section is only used to strengthen the understanding of the background of the present disclosure, and therefore it may include information that does not constitute the prior art known to those of ordinary skill in the art. Summary of the Invention

[0006] The purpose of the present disclosure is to provide a design method for a characteristic simulation component of a turbine blade root trailing edge and the characteristic simulation component, so as to simplify its design process, reduce the processing cost and test difficulty, and can better simulate the stress concentration phenomenon during testing, avoid damage to non-target regions, and ensure the accuracy of the test results.

[0007] To achieve the above invention purpose, the present disclosure adopts the following technical solutions:

[0008] According to a first aspect of the present disclosure, a method for designing a characteristic simulation part of the trailing edge of a turbine blade root is provided. The characteristic simulation part of the trailing edge of the turbine blade root includes a connected blade body characteristic section and a trailing edge characteristic section of the blade root. The method may include: performing a static strength analysis on the turbine blade to obtain a first analysis result, and acquiring the geometric parameters of the turbine blade; statistically analyzing a first characteristic change curve of the blade body in the turbine blade according to the first analysis result, and designing variable cross-section parameters with the first characteristic change curve as the design target, where the first characteristic change curve is used to characterize the change characteristic of the cross-section average stress of the blade body with the height of the blade body; determining the stress-strain distribution and stress gradient path of the dangerous part of the trailing edge of the blade root in the turbine blade according to the first analysis result, and designing chamfer parameters according to the stress-strain distribution of the dangerous part, the stress gradient path, and the geometric parameters; constructing the blade body characteristic section according to the variable cross-section parameters, and constructing the trailing edge characteristic section of the blade root according to the chamfer parameters to obtain a geometric model of the characteristic simulation part of the trailing edge of the turbine blade root; adjusting the geometric model according to the first analysis result, and completing the design of the characteristic simulation part of the trailing edge of the turbine blade root based on the geometric model when the second analysis result and the first analysis result meet the preset design conditions, where the second analysis result is obtained by performing a static strength analysis on the geometric model.

[0009] Optionally, statistically analyzing a first characteristic change curve of the blade body in the turbine blade according to the first analysis result, and designing variable cross-section parameters with the first characteristic change curve as the design target includes: dividing the blade body in the turbine blade into two or more blocks along the height of the blade body; statistically analyzing the unit average stress in each block according to the first analysis result as the cross-section average stress corresponding to the block; plotting the first characteristic change curve with the height of the blade body corresponding to the block as the horizontal axis and the cross-section average stress as the vertical axis; and designing the change rate of the variable cross-section width with respect to the variable cross-section height with the first characteristic change curve as the design target.

[0010] Optionally, determining the stress-strain distribution and stress gradient path of the dangerous part of the trailing edge of the blade root in the turbine blade according to the first analysis result, and designing chamfer parameters according to the stress-strain distribution of the dangerous part, the stress gradient path, and the geometric parameters includes: plotting a stress nephogram of the turbine blade according to the first analysis result; determining the dangerous part in the trailing edge of the blade root according to the stress nephogram, and acquiring the stress-strain distribution and the maximum stress in the dangerous part; determining the stress gradient path along the gradient direction of the maximum stress on the stress nephogram; plotting a second characteristic change curve according to the stress gradient path, where the second characteristic change curve is used to characterize the change characteristic of the maximum stress value in the stress gradient path with the path length; and designing chamfer parameters with the second characteristic change curve as the design target according to the stress-strain distribution of the dangerous part and the geometric parameters.

[0011] Optionally, adjust the geometric model according to the first analysis result, and when the second analysis result and the first analysis result meet the preset design conditions, complete the design of the feature simulation part of the trailing edge of the blade root of the turbine blade based on the geometric model, including: performing a static strength analysis on the geometric model to obtain the second analysis result, and comparing the first analysis result with the second analysis result; when the second analysis result and the first analysis result do not meet the preset design conditions, adjust the geometric model according to the comparison result, and loop through the above steps; when the second analysis result and the first analysis result meet the preset design conditions, complete the design of the feature simulation part of the trailing edge of the blade root of the turbine blade based on the geometric model.

[0012] Optionally, the feature simulation part of the trailing edge of the blade root of the turbine blade further includes a first clamping end, a transition fillet section, and a second clamping end. Construct the blade body feature section according to the variable cross-section parameters, and construct the trailing edge feature section of the blade root according to the chamfer parameters to obtain the geometric model of the feature simulation part of the trailing edge of the blade root of the turbine blade, including: setting the first cross-section; stretching the first cross-section parallel to the stretching direction to the second cross-section to form a first rectangular cube, and opening a pin hole at the center of the first rectangular cube to form the first clamping end; setting the third cross-section on the second cross-section, and stretching the third cross-section parallel to the stretching direction to the fourth cross-section to form a second rectangular cube, the thickness of the second rectangular cube being smaller than the thickness of the first rectangular cube; performing a rolling ball fillet on the edge of the second rectangular cube to form a filleted edge to obtain the trailing edge feature section, the third cross-section, the fourth cross-section, and the rolling ball being set according to the chamfer parameters; sweeping the fourth cross-section along the stretching direction according to the variable cross-section parameters to the fifth cross-section to obtain the blade body feature section; drawing a transition fillet sketch with the fifth cross-section as the reference along the stretching direction, and stretching the fifth cross-section to the sixth cross-section according to the transition fillet sketch to form a transition fillet section; stretching the sixth cross-section parallel to the stretching direction to the seventh cross-section to form a third rectangular cube, and opening a pin hole at the center of the third rectangular cube to form the second clamping end.

[0013] According to the second aspect of the present disclosure, there is provided a feature simulation part of the trailing edge of the blade root of a turbine blade, wherein the feature simulation part of the trailing edge of the blade root of the turbine blade includes a connected trailing edge feature section and a blade body feature section; the trailing edge feature section is used to simulate the stress distribution characteristics at the chamfer position of the trailing edge of the blade root in the turbine blade through a chamfer structure; the blade body feature section is used to simulate the variation characteristics of the cross-section average stress of the blade body with the blade body height in the turbine blade through a variable cross-section.

[0014] Optionally, the feature simulation part of the trailing edge of the blade root of the turbine blade further includes a first clamping end, a transition fillet section, and a second clamping end. The first clamping end is connected to the trailing edge feature section of the blade root, the transition fillet section is connected to the blade body feature section, the second clamping end is connected to the transition fillet section, and the thickness of the first clamping end is greater than the thicknesses of the trailing edge feature section of the blade root, the blade body feature section, the transition fillet section, and the second clamping end; the first clamping end is a rectangular cube structure.

[0015] Optionally, the feature simulation part of the trailing edge of the blade root of the turbine blade is obtained by the design method of the feature simulation part of the trailing edge of the blade root of the turbine blade in the above first aspect.

[0016] The design method of the feature simulation part of the trailing edge of the blade root of the turbine blade provided by the present disclosure obtains a first analysis result through the static strength analysis of the turbine blade and acquires its geometric parameters; then, according to the first analysis result, the first characteristic change curve of the blade body in the turbine blade is statistically analyzed, and the variable cross-section parameters are designed with the first characteristic change curve as the design target. The first characteristic change curve is used to characterize the change characteristic of the cross-section average stress of the blade body with the height of the blade body; and according to the first analysis result, the stress-strain distribution and the stress gradient path of the dangerous part of the blade root in the turbine blade are determined, so as to design the chamfer parameters according to the stress-strain distribution, the stress gradient path, and the geometric parameters of the dangerous part; furthermore, the blade body feature section is constructed according to the variable cross-section parameters, the trailing edge feature section of the blade root is constructed according to the chamfer parameters, and the geometric model of the feature simulation part of the trailing edge of the blade root of the turbine blade is obtained; on this basis, the geometric model is adjusted according to the first analysis result, and when the second analysis result and the first analysis result meet the preset design conditions, the design of the feature simulation part of the trailing edge of the blade root of the turbine blade is completed based on the geometric model, where the second analysis result is obtained through the static strength analysis of the geometric model. In the solution of the present disclosure, when constructing the blade body feature section, the change characteristic of the cross-section average stress of the blade body with the height of the blade body is represented by the variable cross-section design, and when constructing the trailing edge feature section of the blade root, the geometric features and the stress, strain distribution, maximum stress gradient and other features of its dangerous part are combined, which can simplify the design, reduce the processing cost, accurately characterize the stress concentration phenomenon in the test of the simulation part, effectively avoid the damage of the non-target area, reduce the test difficulty, and improve the test accuracy. Description of the Drawings

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0018] Figure 1Shows a schematic structural diagram of a turbine blade.

[0019] Figure 2 Shows a flowchart of the steps of the design method of the characteristic simulation part of the root trailing edge of the turbine blade provided by the embodiments of the present disclosure.

[0020] Figure 3 Shows a schematic diagram of the variable cross-section parameter design process provided by the embodiments of the present disclosure.

[0021] Figure 4 Shows a schematic diagram of the block division of the blade along the blade height provided by the embodiments of the present disclosure.

[0022] Figure 5 Shows one of the schematic diagrams of the first characteristic change curve provided by the embodiments of the present disclosure.

[0023] Figure 6 Shows a schematic diagram of the chamfer parameter design process provided by the embodiments of the present disclosure.

[0024] Figure 7 Shows the equivalent stress nephogram at the root chamfer of the turbine blade provided by the embodiments of the present disclosure.

[0025] Figure 8 Shows one of the schematic diagrams of the stress gradient path provided by the embodiments of the present disclosure.

[0026] Figure 9 Shows one of the schematic diagrams of the second characteristic change curve provided by the embodiments of the present disclosure.

[0027] Figure 10 Shows a schematic diagram of the basic form of the blade feature segment provided by the embodiments of the present disclosure.

[0028] Figure 11 Shows a schematic diagram of the basic form of the root trailing edge feature segment of the turbine blade provided by the embodiments of the present disclosure.

[0029] Figure 12 Shows a schematic flowchart of the steps of constructing a geometric model provided by the embodiments of the present disclosure.

[0030] Figure 13 Shows a schematic structural diagram of the geometric model of the characteristic simulation part of the root trailing edge of the turbine blade provided by the embodiments of the present disclosure.

[0031] Figure 14 Shows a schematic flowchart of the steps of geometric model adjustment provided by the embodiments of the present disclosure.

[0032] Figure 15 Shows a schematic diagram of the block division of the geometric model along the height of the blade feature segment provided by the embodiments of the present disclosure.

[0033] Figure 16Shows the second schematic diagram of the first feature change curve provided by the embodiments of the present disclosure.

[0034] Figure 17 Shows the equivalent stress nephogram of the root trailing edge feature segment provided by the embodiments of the present disclosure.

[0035] Figure 18 Shows the second schematic diagram of the stress gradient path provided by the embodiments of the present disclosure.

[0036] Figure 19 Shows the second schematic diagram of the second feature change curve provided by the embodiments of the present disclosure. Detailed implementation manners

[0037] Example embodiments will now be described more fully with reference to the accompanying drawings. However, the example embodiments can be implemented in various forms and should not be construed as limited to the examples set forth herein; rather, these embodiments are provided so that this disclosure will be more complete and comprehensive, and will fully convey the concept of the example embodiments to those skilled in the art. The described features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. In the following description, numerous specific details are provided to give a thorough understanding of the embodiments of the present disclosure.

[0038] The described features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. In the following description, numerous specific details are provided to give a thorough understanding of the embodiments of the present disclosure. However, those skilled in the art will realize that the technical solutions of the present disclosure may be practiced without one or more of the specific details, or may be implemented using other methods, components, materials, etc. In other cases, well-known structures, materials, or operations are not shown or described in detail to avoid obscuring the main technical concept of the present disclosure.

[0039] When a certain structure is "on" another structure, it may mean that a certain structure is integrally formed on another structure, or that a certain structure is "directly" disposed on another structure, or that a certain structure is "indirectly" disposed on another structure through another structure.

[0040] The terms "a", "an", and "the" are used to denote the presence of one or more elements / components / etc.; the terms "comprising" and "having" are used to mean an open inclusion and mean that there may be additional elements / components / etc. in addition to the listed elements / components / etc. The terms "first" and "second", etc. are used only as labels and are not a limitation on the quantity of their objects.

[0041] Among them, Figure 1 Shows a schematic diagram of the structure of a turbine blade, as Figure 1In the shown turbine blade, it includes a blade body 110, a blade root 120, a shroud 130, a root extension 140 and a tenon 150. It can be seen that if the distance from different positions on the blade body 110 to the shroud 130 is taken as the blade body height at that position, the blade body 110 adopts different cross-sectional shapes at different blade body heights to achieve the aerodynamic performance of the turbine blade; the blade root 120 has a chamfered structure and serves as a transition section between the blade body 110 and the shroud 130. The thickness at the chamfer of the blade root 120 is relatively thin, and high stress areas are likely to be generated during actual operation, thus easily leading to fatigue failure; the shroud 130 is in the shape of a square outward-expanded platform and is connected to the tenon 150 through the root extension 140 as a transition section.

[0042] For Figure 1 Regarding the shown turbine blade, the existing design of the blade root trailing edge simulation part is usually restricted by the geometric features of the turbine blade. The overall design is based on a variable eccentricity pattern. The center of gravity and offset distance of the simulation part are variable, resulting in complex design, high processing cost, and great test difficulty; or, the overall test section is relatively slender, usually with equal width and equal thickness. The geometric feature simulation is not prominent, and the stress concentration phenomenon is not obvious either. Non-target areas may be damaged during the experiment, affecting the accuracy of the test results.

[0043] The present disclosure provides a design method for a characteristic simulation part of a turbine blade root trailing edge, and a characteristic simulation part of a turbine blade root trailing edge designed by this design method. This design method simulates the distribution of the centrifugal load of the blade body of the turbine blade with the blade body height through a variable cross-section, highlighting the simulation of its stress and strain characteristics. During the test process, it can accurately characterize the state of the characteristic simulation part of the turbine blade root trailing edge under different loads, and moreover, it breaks through the limitation of the geometric features of the turbine blade, and can reduce the difficulty and cost in design, processing, and testing, and improve the efficiency. The specific description is as follows with reference to the drawings.

[0044] Figure 2 The flowchart of the steps of the design method for the characteristic simulation part of the turbine blade root trailing edge provided by the embodiment of the present disclosure is shown. The characteristic simulation part of the turbine blade root trailing edge includes a connected blade body characteristic section and a blade root trailing edge characteristic section. As Figure 2 shown, this method may include step 210 to step 250. As follows:

[0045] Step 210: Perform a static strength analysis on the turbine blade to obtain a first analysis result, and obtain the geometric parameters of the turbine blade.

[0046] Among them, the turbine blade is as Figure 1As shown in the figure. As the object to be simulated, the turbine blade can be first subjected to static strength analysis. The static strength analysis can study the characteristics of the turbine blade to withstand and respond to loads under set conditions. Since the turbine blade is affected by various loads and boundary conditions such as centrifugal force, aerodynamics, and temperature during actual operation, the inverse distance weighted average method can be used for temperature and air pressure interpolation, thereby establishing a finite element analysis model of the turbine blade and performing finite element analysis to achieve the static strength analysis of the turbine blade and obtain its first analysis result. The first analysis result can include the stress and strain distribution laws of the turbine blade under loads such as temperature and air pressure.

[0047] In the embodiments of the present disclosure, the geometric parameters of the turbine blade can also be obtained. Among them, according to the design requirements of the simulation part, the geometric parameters can include blade body geometric parameters, flange geometric parameters, etc. It is also possible to obtain the geometric parameters at the maximum equivalent stress point after determining the maximum equivalent stress point according to the first analysis result. The geometric parameters can be length, width, thickness, diameter, cross-sectional area, etc. Those skilled in the art can select the geometric parameters according to actual needs, and the present disclosure does not make specific limitations thereon.

[0048] Step 220: According to the first analysis result, count the first characteristic change curve of the blade body in the turbine blade, and design variable cross-section parameters with the first characteristic change curve as the design target. The first characteristic change curve is used to characterize the change characteristics of the cross-sectional average stress of the blade body with the height of the blade body.

[0049] Among them, according to the stress and strain distribution in the first analysis result, the change characteristics of the cross-sectional average stress of the blade body in the turbine blade with the height of the blade body can be counted. For example, it can include whether the change direction of the interface average stress with the height of the blade body increases or decreases, and whether the change rate is faster or slower as the height of the blade body increases. Optionally, the change characteristics of the cross-sectional average stress of the blade body with the height of the blade body can be characterized in the form of the first characteristic change curve, and this change characteristic can be studied based on the rise, fall, slope, etc. of the first characteristic curve.

[0050] In the present disclosure, the variable cross-section parameters are structural parameters used to represent the variable cross-section. The variable cross-section can refer to a structure in which the cross-section changes unidirectionally, such as the cross-sectional shape, cross-sectional area, etc. changing along the radial direction of the component. On this basis, design variable cross-section parameters with the first characteristic change curve as the design target, so that the change of the variable cross-section can reflect the change characteristics of the cross-sectional average stress of the blade body with the height of the blade body.

[0051] Step 230: According to the first analysis result, determine the stress-strain distribution and stress gradient path of the dangerous part at the trailing edge of the blade root in the turbine blade, and design chamfer parameters according to the stress-strain distribution of the dangerous part, the stress gradient path, and the geometric parameters.

[0052] Among them, the trailing edge of the blade root can refer to the foregoingFigure 1 The relevant description is about the transition section with a chamfered structure between the blade body and the shroud of the turbine blade, which is a high-stress distribution area during operation. The dangerous part refers to the dangerous points, lines, surfaces, etc. where fatigue fracture and damage occur. Usually, the equivalent stress distribution at the trailing edge of the blade root can be calculated according to the first analysis result, and the part with the maximum equivalent stress can be used as the dangerous part. Also, the part with the equivalent stress greater than the safety threshold can be used as the dangerous part. By studying the stress and strain of the dangerous part, the conditions and states under which the component may be damaged in actual applications can be determined.

[0053] In the embodiments of the present disclosure, the stress gradient path is used to characterize the gradient change of the stress in the dangerous part. According to the experimental requirements, the corresponding stress gradient path can be selected. For example, the single search distance of the stress gradient can be set. An arc is drawn with the maximum stress point as the center and the single search distance as the radius, and the minimum principal stress point is determined on this arc. Then, a new arc is drawn with this minimum principal stress point as the center and the single search distance as the radius, and the minimum principal stress point is determined on the new arc. The above path search process is cycled, and the maximum stress point and each minimum principal stress point are connected in the order of the path search to obtain the stress gradient path. At this time, this stress gradient path is the path where the maximum stress gradient in the dangerous part drops the fastest. Among them, the single search distance can be set according to the model size and experimental requirements.

[0054] In the embodiments of the present disclosure, the distribution characteristics of the stress and strain in the dangerous part at the blade root chamfer can be determined through the stress and strain distribution of the dangerous part, and the gradient change of the stress in the dangerous part can be determined through the stress gradient path. On this basis, the chamfer parameters of the characteristic simulation part of the trailing edge of the turbine blade root are designed in combination with the geometric characteristics of the turbine blade, so that the chamfer structure in the characteristic simulation part of the trailing edge of the turbine blade root can effectively simulate the geometric characteristics and stress and strain characteristics at the blade root chamfer.

[0055] Step 240: Construct the blade body characteristic section according to the variable cross-section parameters, and construct the trailing edge characteristic section of the blade root according to the chamfer parameters to obtain the geometric model of the characteristic simulation part of the trailing edge of the turbine blade root.

[0056] Among them, after obtaining the variable cross-section parameters according to Step 220 and the chamfer parameters according to Step 230, the geometric model of the characteristic simulation part of the trailing edge of the turbine blade root can be initially constructed. Among them, the variable cross-section parameters may include the length, width, thickness of the blade body characteristic section, and the change rate of the one-way width with the length, etc. The chamfer parameters may include length, width, thickness, radius at the chamfer, etc.

[0057] In the embodiments of the present disclosure, during the process of constructing the geometric model, the basic form of the blade body feature segment can be determined with the first feature change curve as the design target. For example, the shape of the blade body feature segment, the variation ranges of the length and width, etc. can be preliminarily determined, and the variable cross-section parameters can be designed based on this basic form to construct the specific geometric model of the blade body feature segment part; the same can be applied to the blade root trailing edge feature segment.

[0058] Step 250: Adjust the geometric model according to the first analysis result, and when the second analysis result and the first analysis result meet the preset design conditions, complete the design of the feature simulation part of the blade root trailing edge of the turbine blade based on the geometric model. The second analysis result is obtained by performing a static strength analysis on the geometric model.

[0059] Among them, since the feature simulation part is used to simulate the features at the blade root trailing edge of the turbine blade, the geometric model should perform similarly or identically to the turbine blade in the static strength analysis. On this basis, the geometric model can be adjusted according to the first analysis result, which can be to adjust the variable cross-section parameters, chamfer parameters, etc., so that the second analysis result obtained by performing a static strength analysis on the geometric model and the first analysis result meet the preset design conditions, thereby completing the design of the turbine cooling simulation part based on this geometric model. Moreover, the loads and boundary conditions, etc. used in the static strength analysis of the geometric model should refer to the static strength analysis process of the turbine blade. For example, the boundary conditions can all be uniaxial tensile boundary conditions. In the embodiments of the present disclosure, the preset design conditions can be that the numerical deviation between the first analysis result and the second analysis result is within a certain range, or the curve change trends of the first analysis result and the second analysis result are the same after the same post-processing. Those skilled in the art can specifically set according to the experimental purpose.

[0060] In the embodiments of the present disclosure, the blade body test section adopts a variable cross-section design, which can better simulate the stress characteristics of the blade body, make the position of failure and damage in the experiment more controllable, better simulate the distribution characteristics of the centrifugal load along the blade body height, avoid fractures in non-target areas, and thus improve the efficiency and accuracy of the experiment; moreover, without using an adjustable eccentric style to simulate the stress and strain state, it can also reduce the design, processing, and experimental difficulties, thereby reducing costs and improving efficiency.

[0061] The embodiments of the present disclosure provide a complete design process for the feature simulation part of the blade root trailing edge of the turbine blade, which can effectively simulate the geometric features, stress and strain characteristics, etc. at the blade body and the blade root chamfer, and provide accurate and usable examples for the design, production of the feature simulation part of the blade root trailing edge of the turbine blade, and applications such as the testing of the turbine blade. On this basis, based on the experimental requirements, those skilled in the art can also implement the design of simulation parts for other components based on the blade root trailing edge simulation part design method provided by the present disclosure.

[0062] Figure 3shows a schematic diagram of the variable cross-section parameter design process provided by an embodiment of the present disclosure, as Figure 3 shown, the aforementioned step 220 may include steps 310 to 340. As follows:

[0063] Step 310: Divide the blade body of the turbine blade along the blade height into at least two blocks.

[0064] Step 320: According to the first analysis result, count the average unit stress in each block as the average cross-section stress corresponding to the block.

[0065] Step 330: Draw a first characteristic change curve with the blade height corresponding to the block as the horizontal axis and the average cross-section stress as the vertical axis.

[0066] Step 340: Take the first characteristic change curve as the design target and design the change rate of the variable cross-section width with respect to the variable cross-section height.

[0067] Among them, the blade body of the turbine blade to be simulated can be divided into blocks along the blade height, so that the average unit stress in each block is equivalent to the average cross-section stress corresponding to the block. Optionally, the equivalent cross-section of each block can be the upper surface, the lower surface or the middle cross-section of the block, and then the distance from the equivalent cross-section to the chamfer at the blade root can be used as the blade height corresponding to the block. In an embodiment of the present disclosure, a first characteristic change curve can be further drawn with the average cross-section stress corresponding to the block and the blade height, for example, with the blade height corresponding to the block as the horizontal axis and the average cross-section stress corresponding to the block as the vertical axis, to draw a first characteristic change curve reflecting the change characteristics of the average cross-section stress with the blade height.

[0068] In an embodiment of the present disclosure, the variable cross-section parameters may include the variable cross-section width, the variable cross-section height, and the change rate of the variable cross-section width in the direction of the variable cross-section height. The variable cross-section parameters are designed with the first characteristic change curve as the design target, so that the change rate of the variable cross-section width with respect to the variable cross-section height can reflect the change characteristics of the average cross-section stress with the blade height in the first characteristic change curve, so that the variable cross-section structure of the characteristic section of the blade body can better highlight the stress characteristics of the blade body in the turbine blade.

[0069] Figure 4 shows a schematic diagram of the block division of the blade body along the blade height provided by an embodiment of the present disclosure, as Figure 4 shown, on the basis of the turbine blade shown in Figure 1 shown, the blade body 410 is evenly divided into 9 blocks, and the average unit stress in each block is counted as the average cross-section stress corresponding to the block.

[0070] Figure 5 shows one of the schematic diagrams of the first characteristic change curve provided by an embodiment of the present disclosure, as Figure 5As shown, a first characteristic change curve is plotted with the blade height corresponding to the block as the horizontal axis and the average cross-sectional stress corresponding to the block as the vertical axis. Among them, the blade height is represented by the distance from the relative flange, and after normalizing this distance, it is marked as "normalized distance" on the horizontal axis and "average stress" on the vertical axis.

[0071] Figure 6 The figure shows a schematic diagram of the chamfer parameter design process provided by an embodiment of the present disclosure. As Figure 6 shown, the aforementioned step 230 may include steps 610 to 650. As follows:

[0072] Step 610: Draw a stress nephogram of the turbine blade according to the first analysis result.

[0073] Step 620: Determine the dangerous part in the trailing edge of the blade root according to the stress nephogram, and obtain the stress-strain distribution and the maximum stress in the dangerous part.

[0074] Step 630: Determine the stress gradient path along the gradient direction of the maximum stress on the stress nephogram.

[0075] Step 640: Draw a second characteristic change curve according to the stress gradient path. The second characteristic change curve is used to characterize the change characteristic of the numerical value of the maximum stress in the stress gradient path with the path length.

[0076] Step 650: Design the chamfer parameter with the second characteristic change curve as the design target according to the stress-strain distribution and geometric parameters of the dangerous part.

[0077] Among them, the stress nephogram can be an equivalent stress nephogram, a stress reserve coefficient nephogram, etc. The equivalent stress nephogram can characterize the equivalent stress distribution of the turbine blade, and the stress reserve coefficient nephogram can characterize the relationship between the stress-strain distribution under the actual working state of the turbine blade and the stress-strain distribution under the fatigue failure state. Thus, the dangerous parts prone to fracture on the turbine blade can be determined according to the stress nephogram, and further the stress and strain distribution in the dangerous parts can be determined. Optionally, TECPLOT can be used to post-process the first analysis result to draw the stress nephogram.

[0078] In the embodiment of the present disclosure, after determining the dangerous part, the maximum stress in the dangerous part can be determined, and the stress gradient path of the maximum stress can be determined along the gradient direction. Among them, the gradient direction can be the direction in which the maximum stress gradient drops fastest. For reference, the relevant description of the aforementioned step 230 can be referred to. To avoid repetition, it will not be elaborated here.

[0079] In the embodiments of the present disclosure, the value of the maximum stress on the stress gradient path changes in a gradient manner with the change of the path length. On this basis, its change characteristics can be characterized by a second characteristic change curve. For example, a curve can be plotted with the path length of the stress gradient path as the horizontal axis and the value of the maximum stress as the vertical axis, so as to represent the decrease amplitude, decrease rate, etc. of the value of the maximum stress through the trend, slope, etc. of the curve.

[0080] In the embodiments of the present disclosure, the chamfer parameters can be designed based on the geometric parameters of the turbine blade and with the second characteristic change curve as the design target, so as to simulate the stress gradient and stress distribution at the root chamfer of the turbine blade.

[0081] Figure 7 The equivalent (Mises) stress nephogram at the root chamfer provided by the embodiments of the present disclosure is shown, as Figure 7 shown, there is a stress concentration phenomenon at the root 720 part in the shape of a chamfer on the rim plate 710. Specifically, at the trailing edge split part 721 of the root 720, the equivalent stress distribution is between 649.037 and 972.000.

[0082] Among them, the trailing edge split part 721 is a kind of processing seam in the turbine blade. In actual operation, the cooling air flow enters through the holes at the bottom of the dovetail groove of the turbine blade, and after sufficient heat exchange in the serpentine channel inside the blade body, it is ejected from the film holes at the leading edge and the trailing edge split of the trailing edge turbulators at the root.

[0083] Figure 8 One of the schematic diagrams of the stress gradient path provided by the embodiments of the present disclosure is shown, as Figure 8 shown, on the basis of the equivalent stress nephogram shown in Figure 7 starting from the maximum stress point 810 on the trailing edge split part, search for the stress gradient path 820 with the fastest decrease in the maximum stress gradient. Among them, the stress gradient path 820 includes nodes 250537, 216926, 216892, 247599, 105814, 86407, and these numerical numbers are the node coordinates determined at each step during the path search process.

[0084] Figure 9 One of the schematic diagrams of the second characteristic change curve provided by the embodiments of the present disclosure is shown, as Figure 9 shown, with Figure 9 the path length of the stress gradient path shown as the horizontal axis and the value of the stress corresponding to the path length as the vertical axis, a second characteristic change curve is plotted. Among them, after normalizing the path length, it is marked as "normalized distance" on the horizontal axis and "stress" on the vertical axis.

[0085] In a method embodiment of the present disclosure, the basic form of the blade body feature segment can be determined first, and then relevant variable cross-section parameters can be designed according to the first feature change curve. For example, according to the direction of decreasing centrifugal stress on the blade body of the turbine blade, the variable cross-section stress of the blade body feature segment decreases in the corresponding direction, that is, the basic form of the blade body feature segment can be that along the direction of decreasing centrifugal stress, the variable cross-section width of the blade body feature segment gradually increases with the variable cross-section length. On this basis, the variable cross-section parameters can be determined with the first feature change curve as the design target.

[0086] Figure 10 The schematic diagram of the basic form of the blade body feature segment provided by the embodiment of the present disclosure is shown, such as Figure 10 As shown, for the blade body 1010 of the turbine blade, the centrifugal stress decreases in the direction indicated by the arrow, then the variable cross-section stress of the blade body feature segment 1020 of the feature simulation part at the trailing edge of the blade root of the turbine blade decreases in the direction indicated by the arrow to simulate the state of decreasing centrifugal stress. Thus, the basic form of the blade body feature segment is determined to be that the variable cross-section width gradually increases with the variable cross-section length.

[0087] By analogy, the basic form of the blade root trailing edge feature segment can also be determined first, and then relevant chamfer parameters can be designed according to the second feature change curve. Among them, in the feature simulation of the blade root chamfer, its basic form can be determined based on geometric features, such as the blade body geometric features, the shroud geometric features respectively connected above and below at the blade root chamfer, and the geometric features of the stress concentration area in the blade root chamfer, etc., so as to comprehensively consider its geometric and stress features. On the basis of this basic form, the chamfer parameters can be determined with the second feature change curve as the design target.

[0088] Figure 11 The schematic diagram of the basic form of the blade root trailing edge feature segment provided by the embodiment of the present disclosure is shown, such as Figure 11 As shown, for the blade root 1110 of the turbine blade, the geometric feature 1111 at the maximum equivalent stress point, the shroud geometric feature 1112 and the blade body geometric feature 1113 are selected at the chamfer; in the blade root trailing edge feature segment 1120, according to the selected geometric feature 1111 at the maximum equivalent stress point, the shroud geometric feature 1112 and the blade body geometric feature 1113, the basic form 1121 at the maximum equivalent stress point, the basic form 1122 of the shroud and the basic form 1123 of the blade body are determined.

[0089] Figure 12 The schematic diagram of the step flow for constructing the geometric model provided by the embodiment of the present disclosure is shown, such as Figure 12 As shown, the feature simulation part of the blade root trailing edge of the turbine blade further includes a first clamping end, a transition fillet section and a second clamping end.

[0090] Among them, in order to enable the turbine cooling simulation component to be applied in the test, the feature simulation component at the trailing edge of the blade root of the turbine blade may further include a first clamping end, a transition fillet section, and a second clamping end. The first clamping end may be connected to the feature section at the trailing edge of the blade root, and the transition fillet section may be connected to the blade body feature section and the second clamping end respectively. Thus, by clamping the first clamping end and the second clamping end, a load can be applied to the feature simulation component at the trailing edge of the blade root of the turbine blade for testing.

[0091] Then, the aforementioned step 240 may include steps 1210 to 1270. As follows:

[0092] Step 1210, set a first cross-section.

[0093] Among them, the first cross-section is the reference plane for constructing the geometric model. Based on this reference plane, in the geometric model, the first cross-section is the side surface of the first clamping end away from the second clamping end.

[0094] Figure 13 The schematic diagram of the geometric model structure of the feature simulation component at the trailing edge of the blade root of the turbine blade provided by the embodiment of the present disclosure is shown. As Figure 13 shown, in the process of constructing this geometric model, the first cross-section 1310 can be first set as the reference plane.

[0095] Step 1220, stretch the first cross-section parallel to the stretching direction to a second cross-section to form a first rectangular cube, and open a pin hole at the center of the first rectangular cube to form the first clamping end.

[0096] In the embodiment of the present disclosure, the stretching direction refers to the direction in which the first clamping end extends towards the second clamping end. Stretch the first cross-section parallel to the stretching direction to the second cross-section, thereby forming a first rectangular cube, and open a pin hole at the center of the first rectangular cube to obtain the first clamping end. The first clamping end can be clamped and fixed through this pin hole. Among them, the second cross-section is the same as the first cross-section, and its parameters can be set according to the flange of the turbine blade.

[0097] It should be noted that the processing reference refers to the reference points, reference lines, reference planes, etc. used for assembly, measurement, and positioning during the blanking and subsequent processing of components. When processing components, the position and size of the reference plane should be determined first to ensure the overall processing accuracy of the components and make the processed components meet the design expectations. In the existing design solutions, using a square outward-extending platform to simulate the geometric characteristics of the flange not only easily causes fractures in non-target areas, but also requires material removal processing on both sides in the manufacturing process, resulting in inconsistent processing references, multiple processing steps, high difficulty, and high costs. As a result, the processing accuracy of the existing simulation parts is low, affecting the accuracy of the test results after their application in specific tests. In the embodiments of the present disclosure, the first clamping end is used to simulate the geometric characteristics of the flange, but it is a rectangular cube structure as a whole without an outward-extending platform, which not only effectively simulates the characteristics of the trailing edge of the blade root of the turbine blade, but also in the process preparation, the first clamping end can adopt the overall blanking processing technology, only requiring material removal processing on one side and using the other side as the determined processing reference, reducing the processing steps, simplifying the processing difficulty, and reducing the processing cost. Therefore, the characteristic simulation part of the trailing edge of the blade root of the turbine blade provided by the embodiments of the present disclosure can better control its processing accuracy during actual preparation, ensure the accuracy of the test results after its application in specific tests, and meet the design purpose.

[0098] As Figure 13 shown, the first cross-section 1310 is stretched parallel to the stretching direction to the second cross-section 1320 to form a first rectangular cube, and a pin hole is opened at the center of the first rectangular cube to form the first clamping end a.

[0099] Step 1230: Set a third cross-section on the second cross-section and stretch the third cross-section parallel to the stretching direction to the fourth cross-section to form a second rectangular cube, and the thickness of the second rectangular cube is less than the thickness of the first rectangular cube.

[0100] Among them, the third cross-section is the cross-section where the trailing edge feature section of the blade root is connected to the first clamping end, and the fourth cross-section is the cross-section where the trailing edge feature section of the blade root is connected to the blade body feature section. Stretching the third cross-section to the fourth cross-section forms the second rectangular cube, and the second rectangular cube is the preliminary form of the trailing edge feature section of the blade root. Based on the geometric characteristics of the flange and the blade root chamfer, the thickness of the second rectangular cube is less than the thickness of the first rectangular cube

[0101] Step 1240: Perform ball rolling rounding on the edges of the second rectangular cube to form rounded edges to obtain the trailing edge feature section of the blade root, and the third cross-section, the fourth cross-section, and the ball are set according to the chamfer parameters.

[0102] Among them, after the second rectangular cube is formed, based on the preliminary form of the root trailing edge feature segment, a rolling ball can be used to perform rolling filleting on the edges of the second rectangular cube, so that a chamfer structure is formed on the side of the second rectangular cube to obtain the root trailing edge feature segment, in order to simulate the characteristics at the root chamfer of the turbine blade. On this basis, the positions, widths, lengths of the third cross-section and the fourth cross-section, the radius of the rolling ball, the rolling range, etc. can be determined according to the chamfer parameters.

[0103] As Figure 13 shown, a third cross-section 1330 is set on the second cross-section 1320, and the third cross-section 1330 is stretched to the fourth cross-section 1340 to form a second rectangular cube. A rolling ball with a diameter of 2 mm is used to perform rolling filleting along the four edges of the second rectangular cube to form filleted edges, and the root trailing edge feature segment b is obtained.

[0104] Step 1250: Sweep the fourth cross-section along the stretching direction according to the variable cross-section parameters to the fifth cross-section to obtain the blade body feature segment.

[0105] Among them, during the process of constructing the geometric model, sweeping stretches the contour shape along a specified path to create a three-dimensional solid or a three-dimensional surface. In the embodiments of the present disclosure, during the process of constructing the blade body feature segment, based on the fourth cross-section, the sweeping path, the scale factor, etc. during the sweeping process can be set according to the variable cross-section parameters, so that the constructed blade body feature segment conforms to the stress change characteristics of the blade body of the turbine blade.

[0106] As Figure 13 shown, the control parameters of the sweep are set according to the variable cross-section parameters, and the fourth cross-section 1340 is swept to the fifth cross-section 1350 to obtain the blade body feature segment c.

[0107] Step 1260: Draw a transition fillet sketch in the direction perpendicular to the stretching direction with the fifth cross-section as the reference, and stretch the fifth cross-section to the sixth cross-section according to the transition fillet sketch to form a transition fillet segment.

[0108] Among them, a transition fillet segment can be set between the blade body feature segment and the second clamping end. First, with the fifth cross-section as the reference, a transition fillet sketch can be drawn in the direction perpendicular to the stretching direction to set the width, thickness, length, fillet radian, etc. of the transition fillet segment. Based on this transition fillet sketch, the fifth cross-section is stretched to the sixth cross-section, and then the transition fillet segment between the blade body feature segment and the second clamping end is realized.

[0109] As Figure 13 shown, with the fifth cross-section 1350 as the reference, after drawing a transition fillet sketch in the direction perpendicular to the stretching direction, the fifth cross-section 1350 is stretched to the sixth cross-section 1360 to form a transition fillet segment d.

[0110] Step 1270: Stretch the sixth cross-section parallel to the stretching direction to the seventh cross-section to form a third rectangular cube, and open a pin hole at the center of the third rectangular cube to form the second clamping end.

[0111] Among them, the construction process of the second clamping end can be correspondingly referred to the construction process of the first clamping end in the foregoing step 1220. To avoid repetition, it will not be elaborated here.

[0112] As Figure 13 shown, stretch the sixth cross-section 1360 parallel to the stretching direction to the seventh cross-section 1370 to form a third rectangular cube, and open a pin hole at the center of the third rectangular cube to form the second clamping end e.

[0113] Figure 14 The flowchart of the steps for adjusting the geometric model provided by the embodiment of the present disclosure is shown. As Figure 14 shown, the foregoing step 240 may include step 1410 to step 1430. As follows:

[0114] Step 1410: Perform a static strength analysis on the geometric model to obtain a second analysis result, and compare the first analysis result with the second analysis result.

[0115] Among them, performing a static strength analysis on the geometric model can be referred to the relevant description of the static strength analysis of the turbine blade in the foregoing step 210. To avoid repetition, it will not be elaborated here.

[0116] In the embodiment of the present disclosure, comparing the first analysis result with the second analysis result may be directly comparing the first analysis result with the second analysis result, or performing the same post-processing on the second analysis result as the first analysis result and comparing the processed results. Among them, the post-processing of the second analysis result can be referred to the foregoing Figures 2 to 9 relevant description. To avoid repetition, it will not be elaborated here.

[0117] Figure 15 The schematic diagram of the block division of the geometric model provided by the embodiment of the present disclosure along the height of the blade body feature segment is shown. As Figure 15 shown, the blade body feature segment 1510 is evenly divided into 6 blocks, and the average unit stress in each block is statistically calculated as the cross-section average stress corresponding to the block.

[0118] Figure 16 The second schematic diagram of the first characteristic change curve provided by the embodiment of the present disclosure is shown. As Figure 16 shown, taking the height of the blade body feature segment corresponding to the block as the horizontal axis and the cross-section average stress corresponding to the block as the vertical axis, draw the first characteristic change curve. Among them, the height of the blade body feature segment is represented by the distance relative to the connection of the first clamping end. After normalizing this distance, it is marked as "normalized distance" on the horizontal axis and "stress" on the vertical axis.

[0119] Figure 17 Shows the equivalent (Miese) stress nephogram of the root trailing edge feature segment provided by the embodiments of the present disclosure. As Figure 17 shown, there is a stress concentration phenomenon at the target area 1710 of the root trailing edge feature segment, and the equivalent stress distribution is between 649.499 and 974.033.

[0120] Figure 18 Shows the second schematic diagram of the stress gradient path provided by the embodiments of the present disclosure. As Figure 18 shown, based on the equivalent stress nephogram shown in Figure 17 search for the stress gradient path 2020 with the fastest decline in the maximum stress gradient starting from the maximum stress point 1810. Among them, the stress gradient path 1820 includes nodes 303, 49552, 1538, 49139, 64222, and these numerical numbers are the node coordinates determined at each step during the path search process.

[0121] Figure 19 Shows the second schematic diagram of the second feature change curve provided by the embodiments of the present disclosure. As Figure 19 shown, with Figure 18 the path length of the stress gradient path shown as the horizontal axis and the stress value corresponding to the path length as the vertical axis, draw the second feature change curve. Among them, after normalizing the path length, it is marked as "normalized distance" on the horizontal axis and "stress" on the vertical axis.

[0122] According to the post-processing of the second analysis result described above Figures 15 to 19 compare the geometric model of the feature simulation part of the root trailing edge of the turbine blade and the calculation results of the turbine blade, including the stress distribution in the equivalent stress nephogram, the change trends of the first feature curve and the second feature curve, etc.

[0123] Step 1420: When the second analysis result does not meet the preset design conditions compared with the first analysis result, adjust the geometric model according to the comparison result and loop to execute step 1410.

[0124] Step 1430: When the second analysis result meets the preset design conditions compared with the first analysis result, complete the design of the feature simulation part of the root trailing edge of the turbine blade based on the geometric model.

[0125] Among them, when comparing the first analysis result and the second analysis result, or comparing the post-processing results of the first analysis result and the second analysis result, if their deviation is greater than the preset deviation range, it is determined that the second analysis result does not meet the preset design conditions compared with the first analysis result. At this time, the geometric model can be adjusted according to the comparison result, and the foregoing step 1410 is executed in a loop, and the loop is repeated until the first analysis result and the second analysis result meet the preset design conditions. Optionally, a parametric modeling method can be used to execute the loop optimization process of the geometric model to improve the construction efficiency of the feature simulation part of the trailing edge of the blade root of the turbine blade.

[0126] The design method of the feature simulation part of the trailing edge of the blade root of the turbine blade provided by the present disclosure obtains the first analysis result through the static strength analysis of the turbine blade and obtains its geometric parameters; then, according to the first analysis result, the first characteristic change curve of the blade body in the turbine blade is statistically obtained, and the variable cross-section parameters are designed with the first characteristic change curve as the design target. The first characteristic change curve is used to characterize the change characteristic of the cross-sectional average stress of the blade body with the height of the blade body; and according to the first analysis result, the stress-strain distribution and the stress gradient path of the dangerous part of the blade root trailing edge in the turbine blade are determined, so as to design the chamfer parameters according to the stress-strain distribution, stress gradient path and geometric parameters of the dangerous part; furthermore, according to the variable cross-section parameters, the blade body feature segment is constructed, and according to the chamfer parameters, the blade root trailing edge feature segment is constructed to obtain the geometric model of the feature simulation part of the blade root trailing edge of the turbine blade; on this basis, the geometric model is adjusted according to the first analysis result, and when the second analysis result and the first analysis result meet the preset design conditions, the design of the feature simulation part of the blade root trailing edge of the turbine blade is completed based on this geometric model, wherein the second analysis result is obtained by performing static strength analysis on the geometric model. In the solution of the present disclosure, when constructing the blade body feature segment, the change characteristic of the cross-sectional average stress of the blade body with the height of the blade body is represented by variable cross-section design, and when constructing the blade root trailing edge feature segment, the geometric features and the stress, strain distribution, maximum stress gradient and other features of its dangerous part are combined, which can simplify the design, reduce the processing cost, accurately characterize the stress concentration phenomenon in the test of the simulation part, effectively avoid damage to non-target areas, reduce the test difficulty, and improve the test accuracy.

[0127] It should be noted that although the steps of the method in the present disclosure are described in a specific order in the drawings, this does not require or imply that these steps must be executed in this specific order, or that all the steps shown must be executed to achieve the desired result. Additionally or alternatively, certain steps may be omitted, multiple steps may be combined into one step for execution, and / or one step may be decomposed into multiple steps for execution, etc., all of which should be regarded as part of the present disclosure.

[0128] The embodiment of the present disclosure also provides a structural schematic diagram of the design of the feature simulation part of the trailing edge of the blade root of the turbine blade, as Figure 13As shown, the characteristic simulation part of the root trailing edge of the turbine blade may include a connected root trailing edge characteristic segment b and a blade body characteristic segment c; the root trailing edge characteristic segment b is used to simulate the stress distribution characteristics at the chamfer position on the root of the turbine blade through a chamfer structure; the blade body characteristic segment c is used to simulate the variation characteristics of the cross-sectional average stress of the blade body with the blade body height through a variable cross-section.

[0129] In an embodiment of the present disclosure, the characteristic simulation part of the root trailing edge of the turbine blade further includes a first clamping end a, a transition fillet segment d, and a second clamping end e. The first clamping end a is connected to the root trailing edge characteristic segment b, the transition fillet segment d is connected to the blade body characteristic segment c, and the second clamping end e is connected to the transition fillet segment d. The thickness of the first clamping end a is greater than the thicknesses of the root trailing edge characteristic segment b, the blade body characteristic segment c, the transition fillet segment d, and the second clamping end e; the first clamping end a is a rectangular cube structure.

[0130] In an embodiment of the present disclosure, the characteristic simulation part of the root trailing edge of the turbine blade is obtained through the design method of the characteristic simulation part of the root trailing edge of the turbine blade as described above Figures 2 to 19 shown.

[0131] The characteristic simulation part of the root trailing edge of the turbine blade provided by the present disclosure is obtained through the above design method of the characteristic simulation part of the root trailing edge of the turbine blade. This method obtains the first analysis result through the static strength analysis of the turbine blade and acquires its geometric parameters; then, according to the first analysis result, the first characteristic change curve of the blade body in the turbine blade is statistically obtained, and the variable cross-section parameters are designed with the first characteristic change curve as the design target. The first characteristic change curve is used to characterize the variation characteristics of the cross-sectional average stress of the blade body with the blade body height; and according to the first analysis result, the stress-strain distribution and stress gradient path of the dangerous part of the root trailing edge of the turbine blade are determined, and the chamfer parameters are designed according to the stress-strain distribution, stress gradient path, and geometric parameters of the dangerous part; furthermore, the blade body characteristic segment is constructed according to the variable cross-section parameters, and the root trailing edge characteristic segment is constructed according to the chamfer parameters to obtain the geometric model of the characteristic simulation part of the root trailing edge of the turbine blade; on this basis, the geometric model is adjusted according to the first analysis result, and when the second analysis result and the first analysis result meet the preset design conditions, the design of the characteristic simulation part of the root trailing edge of the turbine blade is completed based on the geometric model, where the second analysis result is obtained through the static strength analysis of the geometric model. In the solution of the present disclosure, when constructing the blade body characteristic segment, the variation characteristics of the cross-sectional average stress of the blade body with the blade body height are represented through variable cross-section design, and when constructing the root trailing edge characteristic segment, combined with geometric characteristics and the stress, strain distribution, maximum stress gradient, etc. of its dangerous part, while simplifying the design and reducing the processing cost, it can accurately characterize the stress concentration phenomenon in the test of the simulation part, effectively avoid damage to non-target areas, reduce the test difficulty, and improve the test accuracy.

[0132] In addition, the above-mentioned drawings are only schematic illustrations of the processes included in the method according to the exemplary embodiments of the present disclosure, rather than for limiting purposes. It is easily understood that the processes shown in the above-mentioned drawings do not indicate or limit the chronological order of these processes. Additionally, it is also easily understood that these processes can be executed, for example, synchronously or asynchronously in multiple modules.

[0133] It should be understood that the present disclosure does not limit its application to the detailed structures and arrangements of the components presented in this specification. The present disclosure is capable of having other embodiments and can be implemented and executed in various ways. The foregoing variations and modifications fall within the scope of the present disclosure. It should be understood that the present disclosure disclosed and defined in this specification extends to all alternative combinations of two or more separate features mentioned or apparent in the text and / or drawings. All such different combinations constitute multiple alternative aspects of the present disclosure. The embodiments of this specification illustrate the best mode known for implementing the present disclosure and will enable those skilled in the art to utilize the present disclosure.

Claims

1. A design method for a characteristic simulation component of the trailing edge of a turbine blade root, characterized in that, the characteristic simulation component of the trailing edge of the turbine blade root includes a connected blade body characteristic section and a trailing edge characteristic section of the blade root, and the method includes: Performing a static strength analysis on the turbine blade to obtain a first analysis result, and acquiring the geometric parameters of the turbine blade; According to the first analysis result, statistically obtaining a first characteristic change curve of the blade body in the turbine blade, and designing variable cross-section parameters with the first characteristic change curve as the design target, where the first characteristic change curve is used to characterize the change characteristic of the cross-section average stress of the blade body with the blade body height; According to the first analysis result, determining the stress-strain distribution and stress gradient path of the dangerous part of the trailing edge of the turbine blade root, and designing chamfer parameters according to the stress-strain distribution of the dangerous part, the stress gradient path, and the geometric parameters; Constructing a blade body characteristic section according to the variable cross-section parameters, and constructing a trailing edge characteristic section of the blade root according to the chamfer parameters to obtain a geometric model of the characteristic simulation component of the trailing edge of the turbine blade root; Adjusting the geometric model according to the first analysis result, and completing the design of the characteristic simulation component of the trailing edge of the turbine blade root based on the geometric model when the second analysis result and the first analysis result meet the preset design conditions, where the second analysis result is obtained by performing a static strength analysis on the geometric model.

2. The method according to claim 1, characterized in that, the step of statistically obtaining a first characteristic change curve of the blade body in the turbine blade according to the first analysis result and designing variable cross-section parameters with the first characteristic change curve as the design target includes: Dividing the blade body in the turbine blade into two or more blocks along the blade body height; According to the first analysis result, statistically obtaining the unit average stress in each block as the cross-section average stress corresponding to the block; Drawing the first characteristic change curve with the blade body height corresponding to the block as the horizontal axis and the cross-section average stress as the vertical axis; Taking the first characteristic change curve as the design target and designing the change rate of the variable cross-section width with respect to the variable cross-section height.

3. The method according to claim 1, characterized in that, the step of determining the stress-strain distribution and stress gradient path of the dangerous part of the trailing edge of the turbine blade root according to the first analysis result and designing chamfer parameters according to the stress-strain distribution of the dangerous part, the stress gradient path, and the geometric parameters includes: Drawing a stress nephogram of the turbine blade according to the first analysis result; Determining the dangerous part in the trailing edge of the blade root according to the stress nephogram, and acquiring the stress-strain distribution and the maximum stress in the dangerous part; Determining the stress gradient path along the gradient direction of the maximum stress on the stress nephogram; Drawing a second characteristic change curve according to the stress gradient path, where the second characteristic change curve is used to characterize the change characteristic of the maximum stress value in the stress gradient path with respect to the path length; Designing the chamfer parameters with the second characteristic change curve as the design target according to the stress-strain distribution of the dangerous part and the geometric parameters.

4. The method according to claim 1, wherein, adjusting the geometric model according to the first analysis result, and when the second analysis result and the first analysis result meet the preset design conditions, completing the design of the characteristic simulation part of the root trailing edge of the turbine blade based on the geometric model, including: performing a static strength analysis on the geometric model to obtain a second analysis result, and comparing the first analysis result with the second analysis result; when the second analysis result and the first analysis result do not meet the preset design conditions, adjusting the geometric model according to the comparison result, and looping to execute the above steps; when the second analysis result and the first analysis result meet the preset design conditions, completing the design of the characteristic simulation part of the root trailing edge of the turbine blade based on the geometric model.

5. The method according to claim 1, wherein, the characteristic simulation part of the root trailing edge of the turbine blade further includes a first clamping end, a transition fillet section and a second clamping end. Constructing the blade body characteristic section according to the variable cross-section parameters and constructing the root trailing edge characteristic section according to the chamfer parameters to obtain the geometric model of the characteristic simulation part of the root trailing edge of the turbine blade, including: setting a first cross-section; parallelly stretching the first cross-section along the stretching direction to a second cross-section to form a first rectangular cube, and opening a pin hole at the center of the first rectangular cube to form a first clamping end; setting a third cross-section on the second cross-section, and parallelly stretching the third cross-section along the stretching direction to a fourth cross-section to form a second rectangular cube, the thickness of the second rectangular cube being smaller than the thickness of the first rectangular cube; performing a ball rolling fillet on the edges of the second rectangular cube with a rolling ball to form a filleted edge, obtaining the root trailing edge characteristic section, the third cross-section, the fourth cross-section, and the rolling ball being set according to the chamfer parameters; sweeping the fourth cross-section along the stretching direction according to the variable cross-section parameters to a fifth cross-section to obtain the blade body characteristic section; drawing a transition fillet sketch with the fifth cross-section as a reference along the stretching direction, and stretching the fifth cross-section to a sixth cross-section according to the transition fillet sketch to form the transition fillet section; parallelly stretching the sixth cross-section along the stretching direction to a seventh cross-section to form a third rectangular cube, and opening a pin hole at the center of the third rectangular cube to form a second clamping end.

6. A characteristic simulation part of the root trailing edge of a turbine blade, wherein, the characteristic simulation part is obtained by the characteristic simulation part design method of the root trailing edge of the turbine blade according to any one of claims 1 to 5, and the characteristic simulation part of the root trailing edge of the turbine blade includes a connected root trailing edge characteristic section and a blade body characteristic section; the root trailing edge characteristic section is used to simulate the stress distribution characteristics at the chamfer position of the root trailing edge in the turbine blade through a chamfer structure; the blade body characteristic section is used to simulate the variation characteristics of the cross-section average stress of the blade body with the blade body height in the turbine blade through a variable cross-section.

7. The characteristic simulation part of the root trailing edge of a turbine blade according to claim 6, wherein, The characteristic simulation part of the trailing edge of the blade root of the turbine blade further includes a first clamping end, a transition fillet section, and a second clamping end. The first clamping end is connected to the trailing edge characteristic section of the blade root, the transition fillet section is connected to the blade body characteristic section, the second clamping end is connected to the transition fillet section, and the thickness of the first clamping end is greater than the thicknesses of the trailing edge characteristic section of the blade root, the blade body characteristic section, the transition fillet section, and the second clamping end; The first clamping end is of a rectangular cube structure.

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